used in
PNG images. Adam7, named after its author, Adam
M. Costello, consists of seven distinct passes over the image.
Each pass transmits a subset of the
pixels in the image.
The pass in which each pixel is transmitted is defined by
replicating the following 8-by-8 pattern over the entire
image, starting at the top left:
1 6 4 6 2 6 4 6
7 7 7 7 7 7 7 7
5 6 5 6 5 6 5 6
7 7 7 7 7 7 7 7
3 6 4 6 3 6 4 6
7 7 7 7 7 7 7 7
5 6 5 6 5 6 5 6
7 7 7 7 7 7 7 7
(2000-09-12)